But how does managing your telecommuters work on a day-to-day basis? Allison O'Kelly, CEO of Mom Corps, a flexible professional staffing agency, manages a 100 percent virtual workforce. Here's her advice for managers:

Train in person. If you're hiring someone into a virtual position, awesome. You can find a great person without having to pay moving expenses! But "training is the most difficult part," says O'Kelly. You have to explain exactly what it is the person needs to do, as well as your culture. "We have had some people who we have tried to train virtually and it really is difficult," O'Kelly says. The solution? Spend time together. O'Kelly is in Pennsylvania, and recently hired a CFO in Atlanta who spent two different weeks with her. Spread out over several weeks, those two weeks have been "invaluable," she says.

Sometimes you do need standing (virtual) meetings. In traditional offices, standing meetings accumulate like clutter. No one knows how they started, but now, even though you see three people all day in the hall, you still have an official meeting with them just because it's Tuesday at 10 a.m. With a virtual workforce, though, "it's very easy, when you don't see people, to fall into your own little world and not really realize that they're there," says O'Kelly. An official daily check-in isn't necessary (unless someone gets a new task every day), but a weekly call keeps everyone on task.

Communicate. Instant messaging is your friend. It's the equivalent of popping into someone's cubicle. You can turn it off when you need to focus, but you'll probably have it on a lot.

Guard your time. The telecommuters who report to you clearly have a relationship with you, so the tendency is for them to ask you questions as they arise, rather than asking colleagues (who they may not see or talk to as much). O'Kelly used to just answer all these emails, but then came up with a better solution. "I needed to draw a hard line about what people should be talking to me about, and what people should be talking to other people about," she says. Now, if someone asks O'Kelly a question that's in someone else's domain, she emails back to say, "Please ask Mary about this," or some such.

Do try to see each other (sometimes). One reason workplaces shy away from telecommuting arrangements is because "there's nothing like a face-to-face meeting," says O'Kelly. But just because in-person meetings are valuable, that doesn't mean you need to be together to get the work done, she adds. Seeing a colleague 40 hours a week is just overkill. Instead, "at least once or twice a year, gather everyone together in one area," O'Kelly says. Locals can get together more often. Seeing each other a few times a year is enough to cement a relationship and still maintain the benefits gained from not battling traffic at rush hour five days a week.